package com.lsht.web.controller.webSocket;

import com.fasterxml.jackson.databind.ObjectMapper;
import com.lsht.common.core.redis.RedisCache;
import lombok.SneakyThrows;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.stereotype.Component;

import javax.websocket.*;
import javax.websocket.server.PathParam;
import javax.websocket.server.ServerEndpoint;
import java.io.IOException;
import java.util.concurrent.CopyOnWriteArraySet;

/**
 * @author zyc
 * @date 2023/05/30 14:20
 */
@Component
@ServerEndpoint(value = "/websocket/{sid}")
@Slf4j
public class WebSocketServer {
    //静态变量，用来记录当前在线连接数。应该把它设计成线程安全的。
    private static int onlineCount = 0;
    //concurrent包的线程安全Set，用来存放每个客户端对应的MyWebSocket对象。
    public static CopyOnWriteArraySet<WebSocketServer> webSocketSet = new CopyOnWriteArraySet<WebSocketServer>();


    //与某个客户端的连接会话，需要通过它来给客户端发送数据
    private Session session;

    //接收sid
    public String sid = "";

    @Autowired
    private RedisCache redisCache;


    /**
     * 连接建立成功调用的方法
     */
    @OnOpen
    public void onOpen(Session session, @PathParam("sid") String sid) {
        this.session = session;
        addOnlineCount();
        log.debug("WebSocket有新窗口开始监听:" + sid + ",当前在线人数为" + getOnlineCount());
        this.sid = sid;
        webSocketSet.add(this);//加入set中
        // 获取查询字符串
        String queryString = session.getQueryString();
        if (queryString != null) {
            System.out.println("Query String: " + queryString);
        }
        try {
//            sendMessage("连接成功");
        } catch (Exception e) {
            log.error("websocket IO异常");
        }
    }

    /**
     * 连接关闭调用的方法
     */
    @OnClose
    public void onClose() {
        webSocketSet.remove(this);  //从set中删除
        subOnlineCount();           //在线数减1
        log.debug("WebSocket有一连接关闭！当前在线人数为" + getOnlineCount());
    }

    /**
     * 收到客户端消息后调用的方法
     *
     * @param message 客户端发送过来的消息
     */
    @OnMessage
    public void onMessage(String message, Session session) {
//        log.info("WebSocket收到来自窗口" + sid + "的信息:" + message);
        //群发消息
//        for (WebSocketServer item : webSocketSet) {
//            try {
//                item.sendMessage(message);
//            } catch (IOException e) {
//                e.printStackTrace();
//            }
//        }
    }

    /**
     * @param session
     * @param error
     */
    @OnError
    public void onError(Session session, Throwable error) {
        log.error("WebSocket发生错误");
//        webSocketSet.remove(this);  //从set中删除
        subOnlineCount();
        error.printStackTrace();
    }

    /**
     * 实现服务器主动推送
     */
    @SneakyThrows
    public void sendMessage(String message) throws IOException {
        this.session.getBasicRemote().sendText(message);
    }


    /**
     * 群发自定义消息
     */
    public synchronized static void sendInfo(Object message, @PathParam("sid") String sid) throws IOException {
        if (message != null) {
            ObjectMapper mapper = new ObjectMapper();
            String message1 = mapper.writeValueAsString(message);
//        log.info("WebSocket推送消息到窗口" + sid + "，推送内容:" + message);
            for (WebSocketServer item : webSocketSet) {
                try {
                    //这里可以设定只推送给这个sid的，为null则全部推送
                    if (sid == null) {
                        item.sendMessage(message1);
                    } else if (item.sid.equals(sid)) {
                        item.sendMessage(message1);
                    }
                } catch (IOException e) {
                    continue;
                }
            }
        }

    }

    public static synchronized int getOnlineCount() {
        return onlineCount;
    }

    public static synchronized void addOnlineCount() {
        WebSocketServer.onlineCount++;
    }

    public static synchronized void subOnlineCount() {
        WebSocketServer.onlineCount--;
    }

}
